645435231331 has 16 divisors (see below), whose sum is σ = 714341058048. Its totient is φ = 578241630400.

The previous prime is 645435231241. The next prime is 645435231341. The reversal of 645435231331 is 133132534546.

It is a cyclic number.

It is not a de Polignac number, because 645435231331 - 2¹⁷ = 645435100259 is a prime.

It is a super-2 number, since 2×645435231331² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (645435231341) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1614066 + ... + 1973848.

It is an arithmetic number, because the mean of its divisors is an integer number (44646316128).

Almost surely, 2^645435231331 is an apocalyptic number.

645435231331 is a deficient number, since it is larger than the sum of its proper divisors (68905826717).

645435231331 is a wasteful number, since it uses less digits than its factorization.

645435231331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 362162.

The product of its digits is 388800, while the sum is 40.

Adding to 645435231331 its reverse (133132534546), we get a palindrome (778567765877).

The spelling of 645435231331 in words is "six hundred forty-five billion, four hundred thirty-five million, two hundred thirty-one thousand, three hundred thirty-one".